A hand setting mechanism corresponding to the general definition which has just been given is well known in the state of the art and is shown for instance in the Swiss patent document No. 462.220. In this document, the non-circular male portion borne by the stem consists of a squared part which may slide in a hole of corresponding form cut into the sliding pinion. As one may see from the cross-section of the figures accompanying the cited patent, the external diameter of the sliding pinion is visibly greater than the diameter of the stem and thus takes up space in the thickness of the timepiece. As may be likewise seen from the same figures, the stem terminates following the squared portion by a circular pivot which turns and slides in an orifice arranged in the base plate. This manner of fabrication leads to a non-negligible space requirement in the sense of the diameter of the base plate which finally brings about an increase in the overall diameter of such base plate.
To overcome the first mentioned difficulty and diminish the thickness of the movement, calibers have already been constructed in which the sliding pinion exhibits an outer diameter of the same order as the diameter of the stem. In order to arrange this, there is cut into the end of the stem a non-circular male portion including two flats engaging in a slit cut into the sliding pinion. This solution, in addition to the advantage which it brings about of reducing the diameter of the said pinion, enables an easy fabrication since the slit is obtained by a simple passage of the milling cutter. Since in the proposed solution, the end of the stem proximate the movement lacks a pivot sliding in a bearing, the sliding pinion has been guided in an orifice cut into the base plate. This orifice however has very thin walls which may be damaged by the flats on the stem if said stem is not sufficiently well guided. The difficulty has been overcome by guiding the stem along a path of greater length at its entry into the base plate on the crown side thereof with the attendant difficulty of occupying at least as much space as if the stem were provided with a pivot sliding in the base plate as was the case in the above cited patent.
To overcome this difficulty and provided a movement the planar space requirement of which is reduced as much as possible, one may employ an arrangement as set forth hereinafter.